1. Field of the Invention
This invention relates generally to packaging systems, and more particularly it concerns a novel dispenser type packaging system in which pellet-like elements such as vials, ampules and the like are held in a secure though easily dispensable manner.
2. Description of the Prior Art
In many instances, particularly in agricultural applications, liquid medications must be shipped and stored at extremely low temperatures, e.g., -140.degree.F. (-95.degree.C.), in order to preserve their effectiveness. This is usually accomplished by packaging the medication in ampules and placing a number of these ampules, one above the other, in a metal rack. Examples of such racks are disclosed in U.S. Pat. Nos. 3,130,836 and 3,207,212. These racks are formed of sheet metal strips with wings or tabs which are bent around to partially encircle the larger diameter portion of the ampules. The tabs are resilient and hold the ampules in place by resilient forces. Also, in order to prevent the ampules from slipping longitudinally in the racks, the racks are formed with tabs which are bent inwardly between adjacent ampules.
A characteristic of these prior art racks is that a substantial portion of each of the ampules is left exposed. Thus, when a number of such racks are stored and transported proximate one another, e.g., in a cryogenic tank, each rack must be enveloped within a protective cardboard tube to prevent breakage of ampules on adjacent racks.
Ampules are dispensed from these prior art racks by forcing them out against the spring retention of the wings or tabs. Often, these ampules are formed with narrow, frangible necks, and the dispensing forces are applied beyond the neck. This concentrates stresses in the ampule neck and causes a danger of possible premature breakage of the ampule. In addition a considerable degree of dexterity is required to remove the ampules without breaking them. These difficulties are compounded by the fact that the ampules are maintained at extremely low temperatures so that they are usually manipulated by persons wearing cryogenic protective gloves.
Further, when an ampule carrier is removed from a cryogenic tank, there may exist deposits of frost which envelop the exposed surfaces of both the rack and the ampules carried by it. These frost deposits further impede ampule removal and increase the danger of breakage because of the excessive transverse forces which must be applied to remove the ampule.